DOXIL® (doxorubicin HCl liposome injection) significantly reduces the side effects associated with doxorubicin. The need to administer DOXIL® only once every 4 weeks by intravenous administration also makes DOXIL® convenient for patients. However, DOXIL® has been shown to not be as effective as doxorubicin. Accordingly, means for increasing the therapeutic efficacy of DOXIL®, while preserving its safety, are desirous.